Star-delta motor controller



June 24, 1947.

f5' 2- "mining:

M MMBHQL Qmmmag l-f" i F. F. .JOHNSON 1 STAR-DELTA' MOTOR CONTROLLER Filed June 22, 1944 in muli Canin! ma j@ r i *uumlr @maling 2 Sheets-She'et 1 n 52W/I5 @par @man Y A'rroRNEYS F. F. JOHNSON STAR-DELTA MOTOR CONTROLLER I June 24, 1947# Filed June 22, 1,944 2 Sheets-Sheet 2 cormun'xr cou-mer A'T Posrrlon Posmon SWITC H capable of operating lbeing detailedly shown in Figs. 2

Patented June 24, 1947 UNITED STATESl PATENT orrics Frederick F. Johnson, Dayton,

General Motors Corporation, corporation of Delaware Ohio, assigner to Detroit, Mich., a

Application filed June 22, 1944, Sei-iai No. 541,515

a claims. (ci. 11a-28o) This invention relates to improvements in the control of reversible, multi-polar electric motors at a plurality of different speeds in either direction.

It is among the objects of the present invention to provide a reversible, multi-polar electric motor with a control device having a single actuating lever adapted to be operated into a plurality of positions in a clockwise direction to cause the motor to operate at a corresponding number of different speeds in one direction and operable into a like number of positions counterclockwise to effect motor operation in a reverse direction at a similar number of speeds.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawingswherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

Fig. 1 is a front view of the assembledcontroller with the cover removed.

Fig. 2 is a plan View of one of the switch elements, 14 similar elements differing only in the arrangement of the lobes on the cam are shown in stacked relation to make up the assembled u t controller shown in Fig. 1.

Fig. 3 is a front edge view of the switch shown in Fig 2.

Fig. 4 is a symbolic showing of the four-pole Y and the eight pole delta phase winding of the electric motor.

Fig. 5 is a similar symbolic showing of the sixpole Y and twelve-pole delta phase winding of the electric motor.

Fig. 6 is a motor connection chart.

Fig. 7 is a chart showing the contacts and operating cams of all fourteen of the switches and indicating at which of the forward or reverse switch positions each switch is closed 'to complete a circuit across it.

Fig. 8 is a diagrammatic view of the switch is moved into positions 1, 2,

switch unit comprises an insulating base 2| having blocks 22, 23 and 24 formed integral therewith. All of these blocks have projecting portions, the one on block 22 being designated by the numeral 22a, the one on block 23 by the numeral 23a and the one on block 2li by the numeral 24a. Corresponding recesses 23h and 24h are provided in the bottom surface of each base 2| so that the projections oi the one switch extend into the recesses of the base of the adjacent switch whereby all switches may properly be stacked.

The block 22 supports a stationary contact member 25 while block 23 supports a similar stationary contact member 26.

A bracket 21 is secured to base 2i in the switch in any suitable manner, this bracket 21 having one end of a flexible contact arm 28 secured thereto. A similar flexible contact arm 29 is secured to a bracket 30 anchored to the base 2i. These contact arms 28 and 29 have inwardly extending lip portions adapted the lobes of a cam 30. All of the cams have a serrated opening for receiving a serrated operating shaft 3i so that rotation of this operating shaft 3l will actuate all of the cams at all of the switches simultaneously.

In Fig. lthe numeral 32 designates a single actuating lever which is secured to the end of the operating shaft'3i extending outside oi the casing 33 of the controller. Within the portion 34 at the top of the switch there is provided any suitable ratchet mechanism for positioning and releasably holding the operating lever 32 when it 3 or 4 clockwise or counterclockwise. These positions are indicated at the top of Fig. 8. All of the switches are secured to the back 35 of the switch casing 23 in any suitable manner so as to be maintained in stacked relation, as shown in Fig. 1.

For purposes of description the switches of the controller are indicated bythe numerals 1 to, 14

assembly and its permanent inter-switch lconnection as well as the terminal connectionwith the motorcircuit indicated similarly in Fig. 9.

Fig. 9 is a diagrammatic view of separate stator windings, the dot-and-dash lines indicating that all windings are secured in a single motor frame unit.

Referring to the drawings and more particularly to Figs. l, 2 and 3 thereof, the numeral 20 designates the entire controller. As has been mentioned in the preamble, this controller comprises fourteen stacked switches, a switch unit and 3. Each inclusive, No. 1 being the top switch unit and No. 14 being the bottom switch unit. All of the fourteen switch units in the controller are substantially identical with the exception of the operat-l ing-cam of each which differs in the following manner, reference being had to the chart shown in Fig. 7. As shown in this chart, the cam of switch No. 1 has four lobes adapted to actuate the right contact of forward operating positions. These lobes actuate the left contact of this switch unit in all iour reverse positions. The cam of the switch No. 2 has four cam lobes which are also adapted to to be engaged by this switch unit ln all four switches Nos. 3, 4, and

close the left contact of this switch unit in response to the operation thereof in all four forward positions. These lobes actuate the right contact in all four reverse positions. The cam of the switch No. 3 has cam lobes diametrically opposite so that both sets of contacts of this switch are closed only in the third position, forward or reverse. The two lobes of the cam of switch No. 4 are so arranged that they will c1ose the left contact of this switch in the second position forward orreverse and the right contacts in the fourth position forward or reverse. Switch No. 5 has the two lobes of its cam so arranged that they will close the left contacts of the switch in the fourth position forward or reverse and the right contacts in the second position forward or reverse. 'I'he-cam of switch No. 6 has four lobes so arranged that the contacts thereof are closed in the first position both forward and reverse. Switch No. '1 has a cam with two lobes so arranged that both contacts of this switch are closed in the third position both forward and reverse. 'I'he cam switch No. 8 has four lobes adapted when actuated in either forward or reverse direction to close the left contact at the first and third position and to close the right contact at the third position. Switch No. 9 has a cam with two lobes so arranged that the left contacts of this switch are closed at the first position forward and reverse. I'he right contact of this switch does not function at any time. Switch No. 10 has a cam with eight lobes adapted to actuate both sets of contacts of this switch in all positions, forward and reverse. 'I'his cam provides double break contacts for line 3, thereby increasing the capacity of the switch. If double break feature is not required, switch sec'- tion No. 10 may be omitted, line 3 would then connect to the jumper 64 and 55 between the movable contacts of sections No. 9 and No. 11. However, the left contacts of this switch are not connected in any circuits and are substantially inactive electrically. Switch section No. 11 has a two-lobe cam so arranged that the left contacts will be closed in the second position forward or reverse and the right contacts in the fourth position forward or reverse. The cam of switch No. 12 has four lobes adapted to close the left contacts as well as the right contacts at the second and fourth positions both forward and reverse. Switch No. 13 has a cam with two lobes adapted to close the left contacts at the fourth position forward or reverse. The right contacts of this switch are electrically inactive. Switch No. 14 has a two-lobe cam adapted like switch No. 13 to close its left contacts at fourth position forward or reverse, the right contacts being electrically inactive.

Reference above to the left contacts including contacts corresponding to those numbered 25 and 28 in Fig. 2 and right contacts are those corresponding to contacts 26 and 28 of Fig. 2.

The Fig. 8 is a diagrammatic view of the switch assembly and its inner and outer electrical connections. By inner connections is meant the connections in the switch between certain contacts thereof, as for instance, stationary contact 125 of switch No. 1 is connected with stationary contact 225 by a strap 40. Similarlycontact |26 of switch No. 1 is connected with contact 226 of switch No. 2 by a strap 41.v The two movable contacts of switch No. 2 are connected together While the movable contacts of switch No. 2 are also connected with the movable contacts of 6 by straps 4I, 44 45 and '12. The right stationary 46 respectively. The two movable contacts of switch No. 1 are connected together and with the movable contacts of switches 3, 4, 5 and 6 by straps 41, 48, 49 and 511, respectively. The two movable contacts o1.' switch No. '1 are connected with each other through strap 51 and with the left movable contact of switch No. 8 by the strap 52. 'I'he right movable contact of switch No. 8 is connected with the right movable contacts of switches Nos. 9, 10 and 11 by straps 52. 54 and 55, respectively. The movable contacts of switch No. 9 are connectedtogether by strap 56 and the two movable contacts of switch No. 11 are connected together by strap 51. The two movable contacts of switch No. 12 are connected together by strap 58 and'also connected with the left movable contact of switches Nos. 13 and 14, by straps 59 and 60. The left movable contact, referred to above, coincides with the contact 28 of the unit shown in Fig. 2, while the right movable contact referred to corresponds to the flexible blade contact 29 of the switch shown in' Fig. 2. For purposes of condensation the group oi' straps 41, 48, 49 and 50 may be referred to by the Roman numeral I. The group including straps 43, 44, 46 and 46 by the Roman numeral II. Straps 53, 64, 55, 56 and 51 by the Roman numeral III. Straps 51 and 52 by the Roman numeral IV and straps 58, 59 and 60 by the Roman numeral V.

The stationary contact |26 of switch No. 1 is connected to the power line. Similarly stationary co'ntact 225 of switch No. 2 is connected to the power line 2. The left stationary contact of switch No. 3 is-marked T6, indicating that it is connected to the lead T6 of stator winding similarly marked as indicated in Fig. 9. The right stationary contact of switch No. 3 is connected to T4 of the lead to the stator winding of the motor.l The left and right stationary contacts of switch No. 4 are connected respectively to the stator leads T11 and T14, as indicated in Fig. 9. The left stationary contact of this switch No. 4 is also connected with the left stationary contact of switch No. 13 by a strap 51. Stationary contacts of the switch No. 5 are connected, the left one to lead T16, the right one to lead T12 of the stator windings, as indicated in Fig. 9. The right stationary contact of switch No. 5 is connected with the left stationary contact of switch No. 14 through the strap 62. The left and right stationary contacts of switch No. 6 are connected to the motor leads T1 and T2 respectively. The left stationary contact of switch No. 6 is also connected with the left stationary contact of switch No. '1 by a strap 6I, while the right stationary contact of switch No. 6 is connected with the right stationary contact of switch No. 7 by a strap 64. The left and right stationary contacts of switch No. 8 are connected with motor leads T3 and T5, as indicated in Fig. 9, the left stationary `contact of this switch No. 8 being connected with the left stationary contact of switch No. 9 by the strap 65. The right stationarycontact of switch No. 10, however, is connected with the power line 3. 'I'he left and right stationary contacts of switch No. 11 are connected with motor leads T15 and T15, as indicated in Fig. 9. The left stationary contact of this switch No. 11 has a strap 66 connecting it with the left stationary contact of switch No. contact of switch No. 12 is connected with the motor lead T11. 'I'he correspondingV contact of switch No. 13 is inactive. However, the left stationary contact of this switch is. as has been previously mentioned,

assasoe i having one portion providing a 4 pole parallel Y and an eight pole series delta.

Fig. shows the motor stator as having also a six pole parallel Y and a twelve pole series delta winding arrangement. Fig. 6 clearly indicates the various connections in order to obtain various speeds. As has been previously mentioned. the actuating lever -32 is adapted to rotate and operate shaft 3i shown in cross section in Fig. 2 and indicated by the dot-and-dash line in Fig. 8, as connecting all the cams of all 14 switches constituting the actuator assembly, this shaft moving the cams in either one direction for reverse motor-movement or in the opposite direction for forward motor operation. This actuating lever 32 when moved into first position forward actuates all of the switch cams and, as indicated in the chart, Fig. 6, under these circumstances the power line LI is connected to the terminal TI; the power line L2 is connected to the terminal T2, while the power line L3 is connected to the terminals T3 and T'I. Terminals T4, T5, TB, TII, TI2, TI3, Til, TIB, TIB and TI1 are unconnected under these circumstances. Now circuit connections are made with a motor causing it to operate at low speed forward.

When lever 32 is actuated to position 2 clockwise LI which is line I is connected with terminal II. L2 with terminal TI2, and L3 with terminals TI 3 and TI1. Now terminals TI and T1 inclusive, Til, TIS and TIB are unconnected. With these circuits complete the motor operates at second speed forward. y

To cause the motor to operate at third speed forward, lever 32 is actuated clockwise to position 3. Now the various cams of the switches are moved so that line I is connected with T6, line 2 with T4 and line 3 with T5. TI, T2, T3 and T1 are connected together by the strap connections 5I, 52, 63 and 64 and switch sections '7 and 8; and TI I to TI1 inclusive are unconnected. Moving the actuator lever 32 clockwise to positicn 4 results in the cams of the switches actuating the various switches to complete the following circuit: Line I to'TI6, line 2 to Til, line 3 to TIB; TI I, TI2, TI3 and TI1 being connected together, and TI to T1 inclusive being unconnected. Now the motor operates at its highest speed.

For reverse operation the actuating lever 32 is moved counterclockwise to positions l, 2, 3 and 4. In all these positions the motor connections are indicated in the diagram, Fig; 6, with the exception that the L2 will occupy the first column to the left now occupied by LI and LI will occupy the top of the second column shown to be occupied by L2. Briey, all motor connections are as indicated in the diagram of Fig. 6 changing the positions of LI and L2 reversely.

'I'he switch unit itself as shown in Fig. 2 is of a well known construction. However, applicant has provided an improved motor controller by assembling 14 of these switches, the strap relation connecting certain elements of certain switches together while maintaining others electrically idle and so arranging the lobes of the cams and the cams themselves on the common cam-actuating member so that the proper connections are made s l strop connection Il leading to l2 connected with a' "tormaybeoperatedata depending with motors of standard design whereby the moplurality of speeds in either direction upon the operation of the switch actuator either clockwise or counterclockwise in the various speed positions.

Applicant has provided a unitary switch controller adapted to be moved clockwise or counterclockwise to obtain operation of the various speeds in either direction. Usually a controller of this type is adapted to be operated in one direction to obtain a plurality of'motor speeds with the motor operating in one direction while the switch unit may be operated only in one position reversely to obtain only a single speed reverse operation of the moto Where a larger number of reverse operations of the motor is desirable it would be necessary to supply additionalswitch units to obtain such motor opera-- tion. As has been said applicant eliminates the necessity of additional switches by so constructing the switch operating cams and arranging the lobes on said cams and the connections between the elements in the switches forming the unit whereby the unit may be operated into a plurality of positions clockwise to obtain a plurality of speeds of the motor operation in one direction and be operated in a plurality of positions counterclockwise to obtain motorl operation at different speeds in a reverse direction.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form,

it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow What is claimed is as follows:

l. A controller for a 3-phase A. C. motor having a stator winding for N pole series-delta operation or for v 2 -pole parallel Y operation and'having end terminals TI1 and TI3 and intermediate terminals TIB. TI2, TIE, TII, TII, N' being a number less than N and greater than said controller havingline terminals l, 2 and 3 and conductors referred to hereinafter by I, II, III, IV, V (IV being connected to T1) and a single controlling member having four positions forward (F) from of! position and four position reverse (R) from oil? position and having fourteen switches variously operated by the controller member for making the following connections: switch 1, line I to conductor I in F positions 1, 2, 3 and 4, line 2 to conductor I in R positions l, 2, 3 and 4; switch 2, line 2 to conductor II in F positions l, 2, 3 and 4, line I to conductor II in R. positions 1, 2, 3 and 4; switch 3, conductor I to T6 and conductor II to T4 in positions 3, F and R; switch 4, conductor I to TII in positions 2, F and R., and conductor II to Til in positions 4, F and R.; switch 5, conductor I to TIB in positions 4, F and R, and conductor II to TI2 in positions 2, F and R; switch 6, conductor I to TI and conductor II to T2 in positions 1, F and R.; switch l conductor IV to TI and T2 inpositions 3, F and R; switch 8,

.motor atl conductor IV to T3 in positions 1, F and R; conductor IV to T3 and conductor III to T5 in positions 3, F and R; switch 9, conductor III to T3 in positions 1, F and Rl; switch 10, line 3 to conductor III in positions 1, 2, 3 and 4, F and R; switch 1l, conductor III to TI3 in positions 2, F and R, and conductor IH to TI in positions 4, F and R; switch 12, conductor V to TI3 and TII in positions 2 and 4, F and R; switch 13, conductor V to TII in positions 4, F and R; and switch 14, conductor V to TI 2 positions 4, F and R.

2. A controller for a four speed, reversible three phase alternating current motor having two stator windings, the one, provided with seven terminal wires, viz: T3, T4, TI, T6, T2, T5 and Tl with equal groups of eld windings connected between each two adjacent terminal wires excepting between the two extreme terminals T3 and T1, certain of said terminals, when connected to a source of three-phase electric current causing the motor to operate as a multi-pole series delta motor at low speed, while other terminal wires of this stator winding, when connected to said source of current and some together, causing the motor to operate as a parallel Y motor at a different or third speed, the second stator winding also having seven terminal wires, viz: TI 1, TI5, TI2, TIS, TII, TH and TI3, with equal groups of pole windings connected between each two adjacent terminal wires excepting the two extremes TI'I and TI3, certain of said terminals, when connected to the'source of electric power causing the motor to operate at second speed as a multi-pole series delta-motor, other terminals, some connected together and others to the source of current, causing the motor to operate at fourth or high speed as a series Y motor, said controller comprising a single operating member rotatable from ofi position into four different positions forward and reverse and having power line terminals I, 2 and 3 and interconnected switching means operated in the rst position forward to connect line I with terminal TI line 2 to terminal T2 and line 3 to terminals T3 and TI, all other terminals being kept open thereby causing the motor to rotate forward as a X-pole series delta motor, whereby when the actuator is moved clockwise into its rst position, power line I will be connected to motor terminal I, power line 2 to motor terminal T2 and power line 3 to both motor terminals T3 and T1, all other motor terminals being kept open by the controller thereby causing the motor to rotate forward, at low speed as a X pole series delta motor; when the actuator is moved clockwise into its second position, the power line I is connected to motor terminal TH, power line 2 to motor terminal TI2 and power line 3A to both motor terminals TI3 and TI 'I, the controller maintaining all other terminal circuits open and thereby causing the motor to rotate forward at second speed as a, Y pole series delta motor; when the actuator is moved clockwise into its third position, the power line I is connected to motor terminal T6, the power line 2 to motor terminal T4 and line 3 to motor terminal T5. Motor terminal TI is connected to T2 and T3 to T'I, the controller maintaining all other motor terminal connections open thereby causing the motor to rotate forward at third speed aS a parallel Y motor, operation of the actuator clockwise into its fourth position causing the convfourth position, line I troller to connect power line I with motor terminal TII, power line 2 with motor terminal TII and line 3 with motor terminal TIE, motor terminals TII and TI2 are connected together as are motor terminals TI3 and T1, all remaining motor terminals are disconnected thereby causing the motor to rotate forward at high or fourth speed as a parallel Y motor; X and Y being different even numbers, return of the actuator to normal "oil" position will actuate the controller to open all circuits and stop the motor; and operation ci the actuator counter-clockwise will operate the controller to reverse only two power line connections as follows: Ilrst position, power line I to motor terminal T2 and line 2 to motor terminal TI;l

second position line I to motor terminal TI2 and line 2 to TI I; third position power line I to motor terminal T4 and line 2 to motor terminal T6; to motor terminal T4 and line 2 to T I6, all other line and motor terminal connections being identical in both directions of motor operation.

3. A controller for a. four speed, reversible three phase alternating current motor having two stator windings, the one, provided with seven terminal wires, viz: T3, T4, TI, T6, T2, T5 and TI with equal groups of field windings connected between each two adjacent terminal wires excepting between the two extreme terminals T3 and T1, certain of said terminals, when connected to a source of three phase electric current causing the motor to operate as a multipole series delta motor at low speed, while other terminal wires of this stator winding, when connected to said source of current and some together, causing the motor to operate as a. parallel Y motor at a different or third speed, the second stator winding also having seven terminal wires, viz: TIT, TIS, TI2, TIS, TII, TH and TI3, with equal groups of pole windings connected between each two adjacent terminal wires excepting the two extremes .T.|'I and TI3, certain of said terminals, when connected to the source of electric power causing the motor to operate at second speed as multi-pole series delta-motor, other terminals, some connected together and others to the source of current, causing the motor to operate at fourth or high speed as a series Y motor, said controller, operative for completing connections to cause the motor to operate at four different speeds in either direction, being a unitary assembly comprising fourteen switch elements secured together in stacked relation, substantially each switch element having active right and left movable contact arms; cooperating right and left stationary contacts engageable by the respective contact arms, and an actuating cam operative clockwise and counter-clockwise to actuate the contact arms into engagement with their respective stationarycontacts at predetermined points in the rotation of the cam, the unitary mechanism having a. common actuator to which all of the cams of the fourteen switches are secured for concurrent rotation, in either direction, into any one of the four positions either side of off position, said unitary control device having a. plurality of separate conductors respectively for making the following connections: the two movable contact arms of switch No. 1 to the left, movable contact arms of the switches Nos. 3, 4, 5` and 6; the two right stationary contacts of switches Nos. 1 andA 2 andr power line I; the two left stationary contacts ci switches Nos. 1 and 2 also power line 2; the two movable contact" arms of switch No. 2 and the right movable contact arms of switches Nos. 3, 4, 5A and 6; the right stationary contacts of switches Nos. 6 and '7 and terminal T2; the left stationary contacts of switches Nos. 6 and 'I and terminal Tl; the two movable contact arms of switch No. 7 and the left movable contact arm of switch No. 8 and terminal T1; the left stationary contacts of switches Nos.' 8 and 9 and terminal T3; the right movable contact arms of switches Nos. 8, 9, 10 and 11 and the left movable arms of -switches No. 9 and No. 11; the left stationary contacts of switches Nos. 11 and 12 together and terminal TH; the movable contact arms of liwitch No. 12 and the left movable contact arms of switches Nos. 13 and 14; the left stationary contact of switch No. 4to which the motor terminal TII is connected, to the left stationary contact of switch No. 13; the left stationary contact of switch No. 14 to the right stationary contact of switch No. 5 to which the motor terminal TI! is also connected; the eft stationary contacts of switches Nos.3 and 5 being connected respectively to -the `motor terminals T6 and TIB; the right stationary contacts of the switches Nos. 3,` 4, 8, 11 and 12 being connected respectively to the motor terminals Tl, Til, T5, T15 and TIT; the right stationary contact of switch No. 10 being connected -to power line 3; the cams of the several switches being constructed for rendering the right and leftpcontacts effective to complete circuits iny th'ej clockwise or forward and the counterclockwise; or reverse positions of the actuator as follows: switch No. 1, right contacts, forward," all fourpositions, left contacts, reverse" all four positions: switch No. 2, right contacts, reverse all four positions, left contacts forward all four positions; switch No. 3, right and left simultaneously closed at third position both forward and reverse; switch No. 4, right contacts fourth position forwar and reverse, left contacts second positionforward and reverse; switch No. 5, right contacts second position both directions, left contacts fourth position both directions; switch No. 6, both sides closed in iirst position, either direction; switch No. '7, both sides closed in third po- REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,264,444 Schmidt ,.Apn 30, 1918 1,335,111 Hellmund `!dar. 30, 1920 1,305,268 Evans June 3, r1919 2,319,503 Glogan May 18, 1943 1,789,085 Seeger Jan. 13, 1931 

